Base: functions and types of structures. Minimum base / plinth height Base / plinth height from ground

The height of the basement is one of the parameters that are of great importance in the construction of a house. This is the lower part of the building, erected on a foundation and fulfilling important functions related to keeping heat indoors. The plinth is necessary in order to protect the walls from the effects of groundwater, it prevents the formation of fungus and mold on the walls, and increases the resistance of the structure to low temperatures. Due to the presence of a plinth, heat transfer between the interior and the street increases.

In order for this part of the house to meet all the requirements and contribute to the solution of the tasks set, it is necessary during construction not only to choose high-quality and reliable material, but also to take into account the height of the basement being erected.

How to determine the height of the base

One of the types of caps is a sinking

The effectiveness of the protective functions that the basement of the house performs directly depends on its height and type:

The protruding base requires additional finishing and the construction of a visor, which protects the structure from precipitation and moisture accumulation. It becomes a decoration for the facade of any building.
The westerner is the most durable. In this version, the joint between the basement and the walls of the house is completely protected from moisture, which is a guarantee of increased safety of the foundation and the protection of the waterproofing layer. During the construction of this type, there is no need to construct obligatory water outlets.
Flush with the wall. The least popular type of base. Requires the construction of a visor, and with additional finishing it becomes bulging.

The choice of the height of the erected basement is influenced by the type of foundation, and the depth of the groundwater, and the climatic conditions in the area where the construction is underway. In addition, it is important to have a basement (basement).

When starting work on the construction of the basement, it is worth considering that the higher it is, the less likely it is that the interior rooms can suffer from moisture penetration. Erections begin directly from the foundation of the house, and at the joints with the walls of the building, the correct organization of waterproofing is required to prevent possible penetration of moisture through the capillaries of the porous material into the walls of the building.

Plinth flush with the wall

The impact on the plinth is comprehensive, since it can withstand the constant load from the walls. And in cases where there is no basement in the house, and the floor is located on the ground, the basement is also subject to the pressure of the ground filled up inside the entire perimeter of the house.

If, in order to determine the width of the future basement, it is necessary to accurately determine the choice of material from which the walls of the house will be erected, and its type depends on the quality of the foundation, then the height will depend on the presence of the basement, temperature, weather conditions and the amount of natural precipitation characteristic of that zone where construction is underway. These parameters differ greatly in different areas, therefore there are no strict guidelines for determining the base / plinth height.

Minimum height

The construction of the basement begins directly from the foundation, and it is raised to a height of at least 40 centimeters. It is believed that this is the minimum height of the basement of the house.

High basement of the house

This height is optimal in the presence of a strip foundation, although a basement of such a height is erected on a different basis, based on the average snow level over a decade that falls annually in this area. A basement of this height is erected only in cases where there is no basement in the house.

In some areas, the height of the basement of the house is lower than this indicator. In especially arid zones, it is allowed to erect a brick structure up to a height of only 20 centimeters. But even here there is a risk of abundant humidification of the walls of the house when ordinary rainwater hits them. In most cases, a properly constructed blind area can change the situation. Although with a low basement height, as well as with improper construction of the foundation, the walls of the house may suffer from capillary moistening of the walls with groundwater. This will lead to the destruction of the material from the inside and a significant reduction in the life of the building.

Standard height

Plinth, standard height

The basement floor requires a significant increase in the height of the basement itself. Now, to the main functions that this design is designed to perform, there is also the provision of installation in the technical room of engineering systems, which include pumps or valves. In some cases, when choosing the height of the basement, they are guided by the height of the basement ceilings.

The features of the construction of the foundation of the house remain important. If the level of the foundation coincides with the level of the ground, then the height of the basement cannot be less than 70 centimeters, and sometimes it reaches one meter. The standard height, when building a country house, reaches 50 or 70 centimeters. It is this value that is recognized as optimal for most areas with various climatic conditions and different depths of groundwater.

So, to determine the height of the basement when building a country house, you must consider:

depth of groundwater;
the amount of precipitation;
the presence of a basement;
the need to organize a technical room in the basement;
view of the equipped base of the house.

Features of waterproofing and insulation at different heights

The efficiency of the strip plinth will be nullified if there are no ventilation ducts in it. These are the holes, the distance between which should not exceed 3 meters. They are arranged around the entire perimeter, providing high-quality air circulation. Internal walls and partitions are no exception. These openings can only be covered with ventilation grilles. In the video you will see how to properly insulate and waterproof the basement of the house.

The use of any plugs is strictly prohibited, since the moisture present in the basement space leads to the formation of mold and mildew. When erecting a brick basement, to organize ventilation ducts, it is enough to leave gaps in the masonry; in other versions, pipes are used that are fixed between the blocks. Jumpers can be sheet steel or conventional fittings.

The waterproofing material provides reliable protection of the basement from groundwater. It can be roofing material or another type of roll waterproofing, such as:

glass roofing material;
rubemast;
euroruberoid.

Lay it in two layers directly on the foundation, applying bituminous mastic or heated bitumen to it. A layer of adhesive is applied between the layers of waterproofing material, providing a strong connection.

What height should the basement of the house be and what does this indicator affect? How to determine the optimal base / plinth height for a wooden house?

Many owners, when building a house with their own hands, doubt whether it is worth paying attention to the height of the basement. Some even believe that it is enough just to build the base to ground level, after which the walls can be erected.

In reality, this is not enough. It should be understood that, to prevent the occurrence of capillary processes in them. The fact is that the humidity of the lower part of the house and the upper part can differ significantly due to the proximity of groundwater, melting snow and many other factors.

As a result, low-lying walls made of wood or porous materials will get wet, which will not only worsen their thermal insulation qualities, but also reduce the service life of the entire structure. The high base of the house will just prevent this process.

Standard height

The optimal height of the basement of a residential building is 35-40 cm. For wooden buildings it is better to make it higher - 50 - 90 cm. For buildings with basements, this value can reach two meters.

When deciding on the height, it is necessary to take into account climatic conditions, such as the average temperature level during the heating season, the amount of snow, etc.

Main functions

Now we will consider all the functions that the above-ground part of the base of the house performs in order to understand what role its height plays:

Note!
The height of the basement of a wooden house is especially important, since rotting of the lower crown is an eternal problem for houses made of logs and beams.
Therefore, it is necessary to build a base of materials resistant to moisture.

The only drawback of a high plinth is that the construction price increases. Therefore, many developers, for reasons of economy, are trying to reduce it. However, such savings are not justified.

Types of plinths

Depending on the type of foundation, the methods of building the basement may vary.

Consider its device on two types of bases:

Tape;
Pile.

On the tape

In the first case, the following types of base are usually made:

Monolithic - the aboveground and underground part of the foundation is a monolithic concrete wall. It is being erected simultaneously with pouring the foundation.
In the form of masonry - in this case, the foundation is erected to the level of the soil, after which the masonry is made of brick or other material. This structure is less protected than a monolithic wall, therefore it needs additional finishing.

On the pile

As a rule, the greatest difficulty during construction is the erection of a basement on a pile foundation. Its height is determined by the above-ground part of the piles.

By the type of device, such a base is of two types:

Suspended construction;
On a tape shallow foundation.

The easiest and cheapest way to make a foundation of the first type. It is based on a crate, which is attached to the piles along the perimeter of the structure. It can be made from wooden beams or metal elements. Further, the crate is sheathed with facing material, for example,.

Note!
The height of the columnar foundation should be at least 20 cm to prevent the possible impact of heaving soil on the building.

The second type of foundation is more difficult to manufacture and costly. Its principle consists in arranging a strip foundation around the perimeter of the room, on top of which the laying is performed. The advantages of this design include the fact that it insulates the structure much better.

In the photo - siding plinth

Finishing the aboveground part of the base

Despite the fact that the high base itself performs a protective function, in order to make the structure more durable, you need to finish it. This will prevent the negative effects of precipitation and, moreover, make the building more beautiful. As an example, consider plinth siding cladding as the most popular material.

Brief instructions for its installation are as follows:

Work begins with the preparation of the walls - it is necessary to eliminate irregularities. If the geometry of the walls is severely disturbed, then it is more expedient to complete the lathing than to level them.
Then the starting strip is mounted, which is installed strictly horizontally, at a height of 40 mm above the lower point of the future cladding.
Then the panel is installed in the guide bar and fixed with self-tapping screws.
Next, the second panel is inserted and shifted to the previous one. It is necessary to leave a small gap in the joints, which will allow the material to expand freely during temperature changes.
Further, the entire remaining area is sheathed in the same way.
At the end of the work on the panels, a finishing bar is installed.

Advice!
To insulate the building, heat-insulating material can be laid under the cladding.

Now the lower part of the house is not afraid of any precipitation and other atmospheric phenomena.

Output

From all of the above, it follows that the higher the base, the fewer problems with heat leakage and the safety of the walls of the house will be in the future. However, the height must be reasonable as it increases the building cost. In this case, it is necessary to take care of the protection of the base itself, finishing it with a reliable material.

For more information on this topic, see the video in this article.

The basement is an external wall rising above ground level, which is a kind of transition between the foundations and the facade of housing construction. This upper part of the building can serve as walls for basements, basements and basements.

The design and construction of the basement part of the building requires a thorough approach. Such parameter as height deserves special attention. A base / plinth that is too low will not be able to protect living quarters from moisture penetration. This negatively affects the integrity and service life of the building, making living impossible.

The base / plinth height depends on the following parameters:

type of base;
house building project;
characteristic features of the soil;
the intended purpose of the basement, if provided.

Construction regulations are also important and cannot be neglected.

The construction costs of the foundation and plinth make up the bulk of the estimate. And if the project does not provide for the presence of a basement, some believe that the base can be made flush with the ground. This, of course, allows you to save on the construction stage, but inevitably harms the building itself. The basement is an indispensable part of houses in the construction of which materials susceptible to moisture are used.

The main function of the basement part of the building is to protect the facade from contact with the ground. The barrier to soil water, lifted through the capillaries from the base, is waterproofing, which is laid directly between the walls of the facade and the basement.

Along with isolating the structure from the effects of groundwater, the following functions are assigned to the base:

protecting the facade from dirt;
protection of the skin from mechanical damage;
compensation for shrinkage under the weight of the structure;
insulation of basement floors from negative influences;
provision of full ventilation and improvement of heat-insulating qualities;

In addition, the basement part gives the house aesthetic appeal and a complete look.

In order for the basement part of the structure to perform all the functions assigned to it, it must have a sufficient height. Otherwise, moisture will penetrate into residential premises, and the facade of the building will remain unprotected from dirt and mechanical stress.

According to building codes and regulations (SNiP), this parameter should not be less than 20 cm. This is the minimum figure. It is better not to save money and erect a basement with a height of 30 to 40 cm. Structures erected from wood are more susceptible to moisture, so the distance above ground level for the lower part should be at least half a meter and reach 90 cm.

The parameter from 20 to 90 cm is the recommended basement height for buildings that do not have a basement in the project. If the house building is being built with a basement floor, it can reach 2 meters. A more accurate indicator of the required height can be calculated taking into account climatic conditions and average precipitation.

It is quite difficult to do this on your own, but it is possible. For this purpose, the average depth of snow cover over several years is calculated, and 10 cm is added to the obtained value. This data can be obtained by analyzing weather forecasts.

Basic types of base

The construction of a high basement leads to an increase in the cost estimate. This is not a reason for saving. The main thing is that the outer wall, which rises above ground level, is strong and has high operational properties.

The height indicator depends not only on the soil, foundation, project, but also on the position of the basement relative to the facade wall. It can be performed in one of the following options:

Westerners.The outer wall is located inside the façade. This option is suitable for buildings with fairly thick walls.
For speakers. The plane of the base is pushed forward. This solution is the only possible option for buildings with thin walls and a basement.
Level. The basement part of the building smoothly passes into the facade, that is, both the upper and lower parts are located in the same plane.

Each of the types has its own characteristic features that affect how the base will be.

How does the type of base affect the height?

The protruding basement is the most costly option, but it is necessary in cases where the project provides for an exploited basement. The height in this case should be maximum. Otherwise, it is impossible to achieve good thermal insulation characteristics. There can be no savings in this case.

For buildings that do not have a basement and basement, it is most advisable to choose the western option. The front overhanging wall becomes the ideal protection of the base of the house from mechanical damage and adverse atmospheric precipitation. The height of such a base is kept to a minimum. The larger it is, the lower the degree of protection.

Basement height and type of foundation

The basement part of the structure on a low foundation (slab, tape, pile-tape) is made of bricks or blocks. The first option is less reliable. Blocks allow you to achieve a higher level of security.

Both base / plinth options require a high-quality finish that provides protective functions. If the groundwater is close, they equip drainage, and if it is low, a blind area. The height of the basement is made no less than the minimum recommended if there is no basement. The minimum indicator is taken solely to save money.

The pile foundation is low if the grillage is right at ground level, and raised. The most unstable is the columnar one, which requires obligatory compensation of soil heaving. For this purpose, the height is made at least 20 cm.

The gaps formed between the posts or piles are laid with bricks, covered with shields or asbestos-cement slabs. The basement cannot be too high due to the design features of the foundation itself.

Basement height when erecting buildings with a basement or basement

Buildings with exploited basements are most widespread in private housing construction. The rationality of such a solution is due to the ability to use this part of the building both for household needs, placing a laundry, pantry, boiler room, cellar in the basement, and for expanding living space, equipping a study, bedroom, gym and so on.

Sometimes both of these appointments are combined. It all depends on the estimated building area. The main thing is that this approach is economically more profitable than adding an additional floor above ground level. The total height of the basement is much higher here than in buildings without a used basement. She, according to SNiP, is at least 250 cm.

The amount by which the basement will rise above ground level depends on the purpose of the basement. If it is supposed to be used as a utility room, it is allowed to take a minimum limit. It is impossible to save money on the basement floor for living rooms, therefore a small margin must be added to the recommended height.

Depending on the type of structure under construction, at the design stage, certain parameters of the foundation are adopted: the area of \u200b\u200bits base, on which the width of the foundation (in the case of a strip base) depends, as well as the height of the foundation above the ground. In this article we will try to give a universal answer to the question of the required foundation height.

Balancing need and redundancy

Considering the fact that the construction of the foundation will make up a considerable share in the costs of building a country house, it is quite understandable that an individual developer wants to minimize the parameters of this part of the building. And if the calculated depth and width of the foundation are parameters that you have to put up with, then with respect to the aboveground height of the foundation, options are possible.

What determines the visible (aboveground) height of the foundation

It is necessary to understand that this part of the base serves as a connecting link, a kind of jumper on the adjacent soil - external environment section. And this area, like no other, during the operation of the building is exposed to external factors - high humidity and temperature fluctuations. The foundation must be raised above the zero mark with the following objectives:

for the device of the basement of the house, when part of the foundation takes on the role of the basement. Obviously, the one-piece structure has better characteristics than the foundation + plinth structure;
to protect the walls of the house from high humidity. Even in spite of the blind area, the lateral lower part of the house will be constantly moistened, so it is better to raise the “foundation - walls” transition as high as possible. How specific? At least 200 mm from the ground, and higher is possible. An observant developer in one of the winters can estimate the thickness of the snow cover on the site, to which you can add 100 mm and get the optimal foundation height;
often the foundation rises above the ground due to the arrangement of the basement. In this case, the height of the base is determined based on the design data;
for columnar and pile foundations, the minimum rise above the ground is also 200 mm, this is required so that the heaving soil does not affect the building. The height can be higher, for example, if the relief of the construction site has a slope;
when calculating the height of the foundation, it is also necessary to take into account the possible shrinkage of the house, the value of which depends on the characteristics of the soil and the load on it from the side of the structure;
an increase in height in some cases prevents the destruction of the material of the walls of the building. This is especially true of wooden buildings, such as baths. In this case, either they immediately arrange a high foundation (about 500 mm), or erect a basement from other building materials.

Summarizing the above

It is necessary to determine the height of the above-ground part of the foundation. We take into account at least 200 mm. We estimate the thickness of the snow cover and, if necessary, change the parameters of the base of the building. The higher the foundation is above the ground, the better and the less effort is required to maintain the lower part of the house. Optimal values \u200b\u200bare considered 350-400 mm above ground level. Do not forget about hydro and thermal insulation of the aboveground part of the foundation! These measures will not only preserve the base of the building (prevent moisture seepage and destruction of the foundation reinforcement), but also reduce heat losses.

Why does a house need a basement?
The basement of the house with two-layer walls.
Features of waterproofing the basement.
Elimination of cold bridges in the basement.

The basement is the aboveground part of the foundation. This is a rather complicated knot, where vertical (basement, walls) and horizontal (floors and ceilings) structures of the house converge and adjoin each other.

Correct construction, waterproofing and insulation of the basement are necessary conditions for the construction of a durable, economical and heat-saving house.

The figure below clearly shows what will happen if the house has a very low basement.

Plinth with a height of at least 20 cm. protects the walls from moisture (in the picture on the left) A low base and the absence of a base leads to dampness of the house wall (in the picture in the center and on the right)

The height of the basement of a private house must be at least 20 cm. With a low plinth, there is a high risk of wetting the wall of the house. The walls will be moistened from splashes when rain drops hit the ground, when snow drifts melt, or from capillary suction of moisture directly from the ground.

Damp walls lose their heat-saving properties. The water freezing in the walls gradually destroys them. Dirt, dampness, mildew and mold appear on the decoration of the walls outside and inside the house.

In areas with high snow cover, it is better to make the basement height not lower than the level of stable snow cover. This rule is especially important for houses with wooden walls.

To protect the walls of the house from moisture emanating from the ground, two lines of defense are created:

Increase the height of the basement in order to remove the walls of the house as far as possible from the ground - a source of moisture.
Arrange waterproofing of the walls of the house and the basement in the dangerous zone of exposure to moisture.

A high plinth increases the cost of building a house. Therefore, depending on the design of the walls and, they try to find a reasonable compromise between the size of the basement and the level of waterproofing.

Be sure to arrange between the basement and the wall of the house ghorizontal layer of roll waterproofing.

In some cases, which are discussed below, it is necessary to do additional waterproofing of the walls of the house.

For a private house it is recommended to make a sinking base... At the sinking plinth, the outer surface of the wall protrudes beyond the border of the plinth by about 50 mm. Water falling on the surface of the wall flows down and falls from the wall past the basement onto the blind area. This solution prevents water flowing down the wall from getting onto the horizontal waterproofing and flowing through it into the wall. For better water drainage a drip is fixed along the lower edge of the wall.

It should be noted that in addition to the moisture protection function, the basement plays a certain role in the architectural appearance of the house. A house on a high plinth looks more solid and impressive, and the decoration of the plinth can emphasize the beauty of the floors of the house.

Correct basement of a house with single-layer exterior walls

The height of the basement of a house with single-layer external walls must be at least 50 cm. (in the picture on the left) Or for a plinth less than 50 cm, but not below 20 cm. , additional waterproofing of the walls is required. (in the picture on the right)

The outer surface of single-layer walls is less protected from moisture than multi-layer walls. Therefore, the basement of a house with a height of at least 50 cm.

If the base of a single-layer wall is below 50 cm.then arrange additional waterproofing in two places:

In the wall, above the first or second layer of masonry made of aerated concrete or porous ceramic blocks, another layer of roll waterproofing is laid.
The outer surface of the wall, in the area of \u200b\u200bthe lower rows of masonry, is protected from water with a layer of vertical waterproofing. To do this, it is enough to use hydrophobic primers and waterproof plasters when decorating the wall. It is better, but more expensive, to cover the basement and the lower part of the walls with a material with low water absorption, for example, clinker tiles.

Plinth construction for a single wall houses with a basement or at home on foundation - slab can

Dimensions of the basement of a house with two-layer outer walls

Minimum base / plinth height for a two-layer wall insulated with expanded polystyrene 20 cm. For a wall insulated with mineral wool, at least 30 cm. (in the left picture) A low base will lead to wetting of the outer finish and soaking of mineral wool insulation (in the picture to the right)

Besides, insulation of the basement eliminates the cold bridge through the basement and the supporting part of the wall, bypassing the thermal insulation of the floor and wall.

In a single-layer wall, the floor is raised to the level of the second or third row of masonry. The vertical waterproofing of the basement is raised to the same level. 2 - waterproofing; 4-5 - plaster on the grid; 8 - finishing; 9 - floor on the ground

If on the site or weakly heaving, then the task of fighting the forces of frost heaving is not worth it. In this case, it is necessary to get rid of only the cold bridge through the base and the supporting part of the wall.

To eliminate the bridge of cold in a house with single walls without insulation of the basement, it is necessary to raise the floor to the level of the second or third row of masonry blocks of the outer wall. This is sufficient, since the material of a single-layer wall has a low thermal conductivity.

The load-bearing part of two- or three-layer walls is usually made of a material with high thermal conductivity. To eliminate the cold bridge in two- or three-layer walls, only the upper part of the base can be closed with insulation, by about 0.5 m. below floor level. This will increase the length of the heat flow path along the plinth.

If the basement space under the house is not heated, then the basement is covered with thermal insulation on both sides.

In multi-layer walls, to eliminate the cold bridge, one outer or both sides of the basement are covered with thermal insulation (for houses with an unheated basement space or floors on the ground)

For multi-layer walls, another way of dealing with the cold bridge is used. The lower rows of masonry of the bearing part of the wall are made of wall material with low thermal conductivity. The floor level is raised in the same way as for a single-layer wall.

For insulation of the basement and the underground part of the foundation, plates of extruded polystyrene foam (penoplex, etc.) are best suited.

It is convenient to insulate strip foundations. The construction of pile foundations with bored (including TISE) or screw piles is more suitable for a cold base. Insulation of such foundations is rather problematic and expensive.

The basement space of houses with pile foundations is usually not insulated. The design of the basement and the floor of the first floor of a house on a pile foundation is chosen taking this circumstance into account.

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